The performance of crystalline silicon n+/p/p+ and n+/n/p+ solar cells under AM0 spectrum, irradiated with 1 MeV electrons at fluences below 1017 cm−2 has been analyzed by means of computer simulation. The software used, fully developed by the authors, solves numerically in one dimension under steady-state conditions, the Poisson and continuity equations self-consistently. The influence of constructive characteristics and different levels of hazardous environmental work conditions on the maximum power point of over 150 devices has been investigated. The study has allowed the authors to propose a useful analytical model related to the constructive characteristics of the device such as polarity, base resistivity and total thickness, with the aim of examining the electrical performance of Si space solar cells. Results presented in this paper are important in order to contribute to the design of radiation-hardened devices.